See algorithms. Build intuition.
Step through data structures and algorithms one decision at a time. At each decision the player stops and asks what happens next.
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16 is smaller than 56, so 56 can only be to the right. Discard 5 values.
Predict Middle value is 16 and the target is 56. What happens next?
One loop, on every topic
Watch
Every step is one change: a comparison, a swap, a pointer move. Step back and forth at your own pace.
Predict
At each decision the player pauses and asks what happens next. Answer, then see.
Understand
The code, the variables and the picture always show the same step, with an explanation of why.
Every topic is a run you step through.
Start anywhere, or follow a track from the beginning.
Data Structures
The containers themselves: how each one is laid out, and which operation that layout makes cheap.Dynamic Programming
Solve each subproblem once, write the answer down, and read it back every other time it is asked for.Tree Algorithms
Walking, searching and rebalancing trees, where the height of the tree sets every cost.Problem-Solving Patterns
The cues in a problem statement that point at a technique, and the check that confirms the technique fits.Linked List Algorithms
Nodes joined by pointers, where every operation comes down to which arrow you move first.Stack and Queue Algorithms
Two rules about which end you are allowed to touch, and the algorithms that fall out of them.
Foundations
The essentials, in an order you can follow from zero.
- 1Array
- 2Binary Search
- 3Two Pointers
- 4Bubble Sort
- 5Insertion Sort
Interview Core
The mainstream set a university course or an interview loop expects, easiest first.
- 1Array
- 2Binary Search
- 3Two Pointers
- 4Bubble Sort
- 5Stable Sorting
The rest of the index
- Complexity Analysis
- Array Algorithms and Techniques
- Sorting
- Mathematics
- String Algorithms
- Bit Manipulation
- Computational Geometry
- Backtracking
- Graph Traversal
- Heap Algorithms
- Connectivity and Topological Order
- Greedy
- Two Pointers
- Algorithmic Paradigms
- Recursion
- Sliding Window
- Range Queries
- Searching
- Shortest Path
- Network Flow
- Hashing
- Divide and Conquer
- Minimum Spanning Tree
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